Didn't realize you were hanging around, Hippo. Welcome back and junk.
About your headache...
If it's a hangover, drink a lot of water, and try to sleep. If you can manage to fall asleep, it should be gone when you wake up.
The Coke thing really only works when you drink significant amounts of caffeine, and haven't had any in a while.
If it's neither, get thee to a pharmacy. Walk, skateboard, drive, whatever. Get ibuprofen. Prescription strength is 800mg, and it's usually prescribed up to 4 times a day. I get bad headaches often, not migraines though, and I've found that 600mg is fine for me. You can get it over the counter and measure accordingly. Usually, I take it just once and I'm good for a few days. Be sure that you're not allergic to it, and be sure to talk with the pharmacist for confirmation. I got my information from a dentist, and I've found that the ibuprofen works better for me than percocet or lortab or pretty much any painkiller that's prescribed for dental work, with no side effects. Just be sure, if you go that route, to eat when you take it as the ibuprofen will probably make you sick on an empty stomach. Above all, talk with your pharmacist before you take anything.
If you're experiencing color flashing, bad sensitivity to light, sound, nausea, etc., go to a doctor.
If it persists for several days, with no fading, go to a doctor.
Hope it gets better. Headaches suck.